1. Field of the Invention
This invention relates to wheel line irrigation systems and particularly to such systems which utilize high volume impact type sprinklers.
2. Description of the Prior Art
Wheel line irrigation systems are well known in the art and are widely used in arid parts of the country for sprinkler irrigation of large areas. A conventional wheel line system includes a series of laterally spaced wheels which carry an irrigation pipeline, on the top of which are mounted a series of sprinklers; each sprinkler operable to cover a circular area of 60 feet in diameter, or an area of approximately 2,826 square feet. The sprinklers are placed 40 feet apart for overlap. The wheel line may be manually moved or self propelled.
Also in the art is a sprinkler of high volume and long reach known under the registered trademark as BIG GUN.RTM.. Such a sprinkler is of the rotary, arm-impact type having a nozzle discharge port of from 0.5" to 0.9". Because of the water demand for such a sprinkler; the torque placed on the pipeline by reactive thrust; and oscillations due to the impact of the high pressure, high volume stream on the impact arm, the sprinkler is presently located only at the terminal outlet end of a conventional sprinkler system, closely adjacent to a support wheel. Mounting of such a sprinkler elsewhere on the pipeline causes destruction of the line because of the effect of the torque and oscillation on the line. The BIG GUN.RTM. type of sprinkler covers a circular area of 250 feet in diameter, or an area of approximately 49,000 square feet--some 17 times the area of conventional sprinklers. The desirability of having a system utilizing such a sprinkler along the length of the pipeline is therefor obvious.